Arc-lamp.



G. GEIGER.

ARC LAMP. APPLICATION FILED AUG. 9, 1909.

1,059, 15 1 Patented Apr. 22, 1913.

4 f L' w J J 1% k 11 f k r 1 l n t ll 53 Z ill GUSTL'VZGEIGER, OI MUNICH, GERMANY.-

Specification of Letters Patent. Application filed August a, 1909. Serial No. 512,031.

Patented Apr. 22, 1913.

with automatical regulation of-the -carbmJS';

automatic pr6- and more particularly tojector lamps.

This invention relates to a selfregulatin projector arc lamp, the construction 0 whichis improved in such a manner that the focus is always maintained at the same point by means of a very simple mechanism. The Y armature of the solenoid in series a s di- 'rectly upon the uppercarboIi-holder and it effects at the same time the movement of the lower carbon-holder by means of a lever connection.

The self regulating arc lamp is shown inthe accompanying drawlngs in partial longitudinal section. In the frame a fixed upon a sit port a the solenoid b is mounted in series. e armature c of the-solerlioid 6 directly operates the upper carbon ho up r end an arm 0 fixed upon the upper end of said armature ,0. The lower end of the carbon-holder (Z is guided in the well known manner upon the ide rod n by means of grooved rollers. he guide rod w forms part of the frame a. The carbon of the upper carbon-holder d (not shown in the drawmgs) is mounted in the sleeve 0. The lower carbon is fixed in the sleeve p of the lower carbon holder k. In the free end of the up r arm. a of the upper carbon holder a r0 7 is fixed the other forkshaped end of which is guided by means of its pin a: in the longitudinal slot t of a two armed lever which is pivoted at n on the frame. Said liver 9 is curved at its middle so as to keep away from the solenoid b. The pusher rod f is guided in a shoulder r of the frame a. The other end of the lever g has a longitudinal slot h with which en- The transmission der d which has at it sgages a pint of a slide a mounted upon the rod w and to which the lower carbon-holder la is fixed. The lower carbon-holderlc therefore moves in unison with theuppe igcarbom holder d and the stabilit of the'focus m is insured. The carbon-ho ders d and k. oscillate like the equal arms of the beam of a balance.

of motiefl in the aris lifted by solenoid when'curi 'e t 'i sdieing' sent through the same, to the two carbon-holders d and k is very simple and the self regulating projector arc lamp1 is distinguished by a very steady light.

T e automatic regulation of the carbons is affected as follows :As long as no current is sent into the lamp the two carbons are in contact but as soon as current is sent into the lamp the carbon holders are moved away the one from the other owing to the upward motion of the armature c. This armature lifts' the upper c'arbon-holder.by means of the supporting arm a and lowers at the same time the lower carbon-holder it through the intermediary of the rod f and of the lever g. The are is produced. As soon as the resistance of the arc increases owing to the burning away of the carbons, theintensit-y of the current which'flows through the solenoid is reduced and the attraction on the armature is decreased and the carbons are permitted to approach each other until the arc and current are again. normal. As the transmission'of the regulatin motion is effected by means of levers whic are rigidly connected with each other, the friction is greatly reduced so that the arc lamp burns with a constant flame even at the low voltage of only 4 amperes.

I claim A self regulating projector are lamp comprising in combination with the frame of the lamp, the solenoid in series, the armature of said solenoid, the upper carbon'holder mounted upon the upper end of said armature so that its upper arm extends to the rear of the frame, a pusher rod fixed to the free end of the upper carbon-holder means for the lower end of said pusher rod, and having a longitudinal slot in its other end, the

lower carbon-holder, a stud projecting from said carbon-holder and engaging with said longitudinal slot of the connecting lever,

substantially as described and shown and for the purpose set forth. 10

In witness whereof I have hereunto set my hand in the presence of two witnesses.

" GUSTAV GEIGER. Witnesses:

LOUIS MUELLER, MATHILDE K. HELD. 

